freebsd-dev/sys/geom/geom_io.c
2019-03-15 22:39:55 +00:00

1096 lines
28 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2002 Poul-Henning Kamp
* Copyright (c) 2002 Networks Associates Technology, Inc.
* Copyright (c) 2013 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Poul-Henning Kamp
* and NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* Portions of this software were developed by Konstantin Belousov
* under sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/ktr.h>
#include <sys/proc.h>
#include <sys/stack.h>
#include <sys/sysctl.h>
#include <sys/vmem.h>
#include <sys/errno.h>
#include <geom/geom.h>
#include <geom/geom_int.h>
#include <sys/devicestat.h>
#include <vm/uma.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/vm_map.h>
static int g_io_transient_map_bio(struct bio *bp);
static struct g_bioq g_bio_run_down;
static struct g_bioq g_bio_run_up;
/*
* Pace is a hint that we've had some trouble recently allocating
* bios, so we should back off trying to send I/O down the stack
* a bit to let the problem resolve. When pacing, we also turn
* off direct dispatch to also reduce memory pressure from I/Os
* there, at the expxense of some added latency while the memory
* pressures exist. See g_io_schedule_down() for more details
* and limitations.
*/
static volatile u_int pace;
static uma_zone_t biozone;
/*
* The head of the list of classifiers used in g_io_request.
* Use g_register_classifier() and g_unregister_classifier()
* to add/remove entries to the list.
* Classifiers are invoked in registration order.
*/
static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook)
g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq);
#include <machine/atomic.h>
static void
g_bioq_lock(struct g_bioq *bq)
{
mtx_lock(&bq->bio_queue_lock);
}
static void
g_bioq_unlock(struct g_bioq *bq)
{
mtx_unlock(&bq->bio_queue_lock);
}
#if 0
static void
g_bioq_destroy(struct g_bioq *bq)
{
mtx_destroy(&bq->bio_queue_lock);
}
#endif
static void
g_bioq_init(struct g_bioq *bq)
{
TAILQ_INIT(&bq->bio_queue);
mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF);
}
static struct bio *
g_bioq_first(struct g_bioq *bq)
{
struct bio *bp;
bp = TAILQ_FIRST(&bq->bio_queue);
if (bp != NULL) {
KASSERT((bp->bio_flags & BIO_ONQUEUE),
("Bio not on queue bp=%p target %p", bp, bq));
bp->bio_flags &= ~BIO_ONQUEUE;
TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue);
bq->bio_queue_length--;
}
return (bp);
}
struct bio *
g_new_bio(void)
{
struct bio *bp;
bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR1(KTR_GEOM, "g_new_bio(): %p", bp);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3);
}
#endif
return (bp);
}
struct bio *
g_alloc_bio(void)
{
struct bio *bp;
bp = uma_zalloc(biozone, M_WAITOK | M_ZERO);
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3);
}
#endif
return (bp);
}
void
g_destroy_bio(struct bio *bp)
{
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3);
}
#endif
uma_zfree(biozone, bp);
}
struct bio *
g_clone_bio(struct bio *bp)
{
struct bio *bp2;
bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
if (bp2 != NULL) {
bp2->bio_parent = bp;
bp2->bio_cmd = bp->bio_cmd;
/*
* BIO_ORDERED flag may be used by disk drivers to enforce
* ordering restrictions, so this flag needs to be cloned.
* BIO_UNMAPPED and BIO_VLIST should be inherited, to properly
* indicate which way the buffer is passed.
* Other bio flags are not suitable for cloning.
*/
bp2->bio_flags = bp->bio_flags &
(BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST);
bp2->bio_length = bp->bio_length;
bp2->bio_offset = bp->bio_offset;
bp2->bio_data = bp->bio_data;
bp2->bio_ma = bp->bio_ma;
bp2->bio_ma_n = bp->bio_ma_n;
bp2->bio_ma_offset = bp->bio_ma_offset;
bp2->bio_attribute = bp->bio_attribute;
if (bp->bio_cmd == BIO_ZONE)
bcopy(&bp->bio_zone, &bp2->bio_zone,
sizeof(bp->bio_zone));
/* Inherit classification info from the parent */
bp2->bio_classifier1 = bp->bio_classifier1;
bp2->bio_classifier2 = bp->bio_classifier2;
#if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
bp2->bio_track_bp = bp->bio_track_bp;
#endif
bp->bio_children++;
}
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3);
}
#endif
return(bp2);
}
struct bio *
g_duplicate_bio(struct bio *bp)
{
struct bio *bp2;
bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO);
bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST);
bp2->bio_parent = bp;
bp2->bio_cmd = bp->bio_cmd;
bp2->bio_length = bp->bio_length;
bp2->bio_offset = bp->bio_offset;
bp2->bio_data = bp->bio_data;
bp2->bio_ma = bp->bio_ma;
bp2->bio_ma_n = bp->bio_ma_n;
bp2->bio_ma_offset = bp->bio_ma_offset;
bp2->bio_attribute = bp->bio_attribute;
bp->bio_children++;
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3);
}
#endif
return(bp2);
}
void
g_reset_bio(struct bio *bp)
{
bzero(bp, sizeof(*bp));
}
void
g_io_init()
{
g_bioq_init(&g_bio_run_down);
g_bioq_init(&g_bio_run_up);
biozone = uma_zcreate("g_bio", sizeof (struct bio),
NULL, NULL,
NULL, NULL,
0, 0);
}
int
g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
{
struct bio *bp;
int error;
g_trace(G_T_BIO, "bio_getattr(%s)", attr);
bp = g_alloc_bio();
bp->bio_cmd = BIO_GETATTR;
bp->bio_done = NULL;
bp->bio_attribute = attr;
bp->bio_length = *len;
bp->bio_data = ptr;
g_io_request(bp, cp);
error = biowait(bp, "ggetattr");
*len = bp->bio_completed;
g_destroy_bio(bp);
return (error);
}
int
g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp)
{
struct bio *bp;
int error;
g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd);
bp = g_alloc_bio();
bp->bio_cmd = BIO_ZONE;
bp->bio_done = NULL;
/*
* XXX KDM need to handle report zone data.
*/
bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args));
if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES)
bp->bio_length =
zone_args->zone_params.report.entries_allocated *
sizeof(struct disk_zone_rep_entry);
else
bp->bio_length = 0;
g_io_request(bp, cp);
error = biowait(bp, "gzone");
bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args));
g_destroy_bio(bp);
return (error);
}
int
g_io_flush(struct g_consumer *cp)
{
struct bio *bp;
int error;
g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name);
bp = g_alloc_bio();
bp->bio_cmd = BIO_FLUSH;
bp->bio_flags |= BIO_ORDERED;
bp->bio_done = NULL;
bp->bio_attribute = NULL;
bp->bio_offset = cp->provider->mediasize;
bp->bio_length = 0;
bp->bio_data = NULL;
g_io_request(bp, cp);
error = biowait(bp, "gflush");
g_destroy_bio(bp);
return (error);
}
static int
g_io_check(struct bio *bp)
{
struct g_consumer *cp;
struct g_provider *pp;
off_t excess;
int error;
biotrack(bp, __func__);
cp = bp->bio_from;
pp = bp->bio_to;
/* Fail if access counters dont allow the operation */
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_GETATTR:
if (cp->acr == 0)
return (EPERM);
break;
case BIO_WRITE:
case BIO_DELETE:
case BIO_FLUSH:
if (cp->acw == 0)
return (EPERM);
break;
case BIO_ZONE:
if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) ||
(bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) {
if (cp->acr == 0)
return (EPERM);
} else if (cp->acw == 0)
return (EPERM);
break;
default:
return (EPERM);
}
/* if provider is marked for error, don't disturb. */
if (pp->error)
return (pp->error);
if (cp->flags & G_CF_ORPHAN)
return (ENXIO);
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
/* Zero sectorsize or mediasize is probably a lack of media. */
if (pp->sectorsize == 0 || pp->mediasize == 0)
return (ENXIO);
/* Reject I/O not on sector boundary */
if (bp->bio_offset % pp->sectorsize)
return (EINVAL);
/* Reject I/O not integral sector long */
if (bp->bio_length % pp->sectorsize)
return (EINVAL);
/* Reject requests before or past the end of media. */
if (bp->bio_offset < 0)
return (EIO);
if (bp->bio_offset > pp->mediasize)
return (EIO);
/* Truncate requests to the end of providers media. */
excess = bp->bio_offset + bp->bio_length;
if (excess > bp->bio_to->mediasize) {
KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 ||
round_page(bp->bio_ma_offset +
bp->bio_length) / PAGE_SIZE == bp->bio_ma_n,
("excess bio %p too short", bp));
excess -= bp->bio_to->mediasize;
bp->bio_length -= excess;
if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
bp->bio_ma_n = round_page(bp->bio_ma_offset +
bp->bio_length) / PAGE_SIZE;
}
if (excess > 0)
CTR3(KTR_GEOM, "g_down truncated bio "
"%p provider %s by %d", bp,
bp->bio_to->name, excess);
}
/* Deliver zero length transfers right here. */
if (bp->bio_length == 0) {
CTR2(KTR_GEOM, "g_down terminated 0-length "
"bp %p provider %s", bp, bp->bio_to->name);
return (0);
}
if ((bp->bio_flags & BIO_UNMAPPED) != 0 &&
(bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 &&
(bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) {
if ((error = g_io_transient_map_bio(bp)) >= 0)
return (error);
}
break;
default:
break;
}
return (EJUSTRETURN);
}
/*
* bio classification support.
*
* g_register_classifier() and g_unregister_classifier()
* are used to add/remove a classifier from the list.
* The list is protected using the g_bio_run_down lock,
* because the classifiers are called in this path.
*
* g_io_request() passes bio's that are not already classified
* (i.e. those with bio_classifier1 == NULL) to g_run_classifiers().
* Classifiers can store their result in the two fields
* bio_classifier1 and bio_classifier2.
* A classifier that updates one of the fields should
* return a non-zero value.
* If no classifier updates the field, g_run_classifiers() sets
* bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls.
*/
int
g_register_classifier(struct g_classifier_hook *hook)
{
g_bioq_lock(&g_bio_run_down);
TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link);
g_bioq_unlock(&g_bio_run_down);
return (0);
}
void
g_unregister_classifier(struct g_classifier_hook *hook)
{
struct g_classifier_hook *entry;
g_bioq_lock(&g_bio_run_down);
TAILQ_FOREACH(entry, &g_classifier_tailq, link) {
if (entry == hook) {
TAILQ_REMOVE(&g_classifier_tailq, hook, link);
break;
}
}
g_bioq_unlock(&g_bio_run_down);
}
static void
g_run_classifiers(struct bio *bp)
{
struct g_classifier_hook *hook;
int classified = 0;
biotrack(bp, __func__);
TAILQ_FOREACH(hook, &g_classifier_tailq, link)
classified |= hook->func(hook->arg, bp);
if (!classified)
bp->bio_classifier1 = BIO_NOTCLASSIFIED;
}
void
g_io_request(struct bio *bp, struct g_consumer *cp)
{
struct g_provider *pp;
struct mtx *mtxp;
int direct, error, first;
uint8_t cmd;
biotrack(bp, __func__);
KASSERT(cp != NULL, ("NULL cp in g_io_request"));
KASSERT(bp != NULL, ("NULL bp in g_io_request"));
pp = cp->provider;
KASSERT(pp != NULL, ("consumer not attached in g_io_request"));
#ifdef DIAGNOSTIC
KASSERT(bp->bio_driver1 == NULL,
("bio_driver1 used by the consumer (geom %s)", cp->geom->name));
KASSERT(bp->bio_driver2 == NULL,
("bio_driver2 used by the consumer (geom %s)", cp->geom->name));
KASSERT(bp->bio_pflags == 0,
("bio_pflags used by the consumer (geom %s)", cp->geom->name));
/*
* Remember consumer's private fields, so we can detect if they were
* modified by the provider.
*/
bp->_bio_caller1 = bp->bio_caller1;
bp->_bio_caller2 = bp->bio_caller2;
bp->_bio_cflags = bp->bio_cflags;
#endif
cmd = bp->bio_cmd;
if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) {
KASSERT(bp->bio_data != NULL,
("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd));
}
if (cmd == BIO_DELETE || cmd == BIO_FLUSH) {
KASSERT(bp->bio_data == NULL,
("non-NULL bp->data in g_io_request(cmd=%hu)",
bp->bio_cmd));
}
if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) {
KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
("wrong offset %jd for sectorsize %u",
bp->bio_offset, cp->provider->sectorsize));
KASSERT(bp->bio_length % cp->provider->sectorsize == 0,
("wrong length %jd for sectorsize %u",
bp->bio_length, cp->provider->sectorsize));
}
g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd);
bp->bio_from = cp;
bp->bio_to = pp;
bp->bio_error = 0;
bp->bio_completed = 0;
KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
("Bio already on queue bp=%p", bp));
if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
binuptime(&bp->bio_t0);
else
getbinuptime(&bp->bio_t0);
#ifdef GET_STACK_USAGE
direct = (cp->flags & G_CF_DIRECT_SEND) != 0 &&
(pp->flags & G_PF_DIRECT_RECEIVE) != 0 &&
!g_is_geom_thread(curthread) &&
((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 ||
(bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) &&
pace == 0;
if (direct) {
/* Block direct execution if less then half of stack left. */
size_t st, su;
GET_STACK_USAGE(st, su);
if (su * 2 > st)
direct = 0;
}
#else
direct = 0;
#endif
if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1) {
g_bioq_lock(&g_bio_run_down);
g_run_classifiers(bp);
g_bioq_unlock(&g_bio_run_down);
}
/*
* The statistics collection is lockless, as such, but we
* can not update one instance of the statistics from more
* than one thread at a time, so grab the lock first.
*/
mtxp = mtx_pool_find(mtxpool_sleep, pp);
mtx_lock(mtxp);
if (g_collectstats & G_STATS_PROVIDERS)
devstat_start_transaction(pp->stat, &bp->bio_t0);
if (g_collectstats & G_STATS_CONSUMERS)
devstat_start_transaction(cp->stat, &bp->bio_t0);
pp->nstart++;
cp->nstart++;
mtx_unlock(mtxp);
if (direct) {
error = g_io_check(bp);
if (error >= 0) {
CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p "
"provider %s returned %d", bp, bp->bio_to->name,
error);
g_io_deliver(bp, error);
return;
}
bp->bio_to->geom->start(bp);
} else {
g_bioq_lock(&g_bio_run_down);
first = TAILQ_EMPTY(&g_bio_run_down.bio_queue);
TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue);
bp->bio_flags |= BIO_ONQUEUE;
g_bio_run_down.bio_queue_length++;
g_bioq_unlock(&g_bio_run_down);
/* Pass it on down. */
if (first)
wakeup(&g_wait_down);
}
}
void
g_io_deliver(struct bio *bp, int error)
{
struct bintime now;
struct g_consumer *cp;
struct g_provider *pp;
struct mtx *mtxp;
int direct, first;
biotrack(bp, __func__);
KASSERT(bp != NULL, ("NULL bp in g_io_deliver"));
pp = bp->bio_to;
KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver"));
cp = bp->bio_from;
if (cp == NULL) {
bp->bio_error = error;
bp->bio_done(bp);
return;
}
KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver"));
KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver"));
#ifdef DIAGNOSTIC
/*
* Some classes - GJournal in particular - can modify bio's
* private fields while the bio is in transit; G_GEOM_VOLATILE_BIO
* flag means it's an expected behaviour for that particular geom.
*/
if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) {
KASSERT(bp->bio_caller1 == bp->_bio_caller1,
("bio_caller1 used by the provider %s", pp->name));
KASSERT(bp->bio_caller2 == bp->_bio_caller2,
("bio_caller2 used by the provider %s", pp->name));
KASSERT(bp->bio_cflags == bp->_bio_cflags,
("bio_cflags used by the provider %s", pp->name));
}
#endif
KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0"));
KASSERT(bp->bio_completed <= bp->bio_length,
("bio_completed can't be greater than bio_length"));
g_trace(G_T_BIO,
"g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd",
bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error,
(intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
("Bio already on queue bp=%p", bp));
/*
* XXX: next two doesn't belong here
*/
bp->bio_bcount = bp->bio_length;
bp->bio_resid = bp->bio_bcount - bp->bio_completed;
#ifdef GET_STACK_USAGE
direct = (pp->flags & G_PF_DIRECT_SEND) &&
(cp->flags & G_CF_DIRECT_RECEIVE) &&
!g_is_geom_thread(curthread);
if (direct) {
/* Block direct execution if less then half of stack left. */
size_t st, su;
GET_STACK_USAGE(st, su);
if (su * 2 > st)
direct = 0;
}
#else
direct = 0;
#endif
/*
* The statistics collection is lockless, as such, but we
* can not update one instance of the statistics from more
* than one thread at a time, so grab the lock first.
*/
if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
binuptime(&now);
mtxp = mtx_pool_find(mtxpool_sleep, cp);
mtx_lock(mtxp);
if (g_collectstats & G_STATS_PROVIDERS)
devstat_end_transaction_bio_bt(pp->stat, bp, &now);
if (g_collectstats & G_STATS_CONSUMERS)
devstat_end_transaction_bio_bt(cp->stat, bp, &now);
cp->nend++;
pp->nend++;
mtx_unlock(mtxp);
if (error != ENOMEM) {
bp->bio_error = error;
if (direct) {
biodone(bp);
} else {
g_bioq_lock(&g_bio_run_up);
first = TAILQ_EMPTY(&g_bio_run_up.bio_queue);
TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue);
bp->bio_flags |= BIO_ONQUEUE;
g_bio_run_up.bio_queue_length++;
g_bioq_unlock(&g_bio_run_up);
if (first)
wakeup(&g_wait_up);
}
return;
}
if (bootverbose)
printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
bp->bio_children = 0;
bp->bio_inbed = 0;
bp->bio_driver1 = NULL;
bp->bio_driver2 = NULL;
bp->bio_pflags = 0;
g_io_request(bp, cp);
pace = 1;
return;
}
SYSCTL_DECL(_kern_geom);
static long transient_maps;
SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD,
&transient_maps, 0,
"Total count of the transient mapping requests");
u_int transient_map_retries = 10;
SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW,
&transient_map_retries, 0,
"Max count of retries used before giving up on creating transient map");
int transient_map_hard_failures;
SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD,
&transient_map_hard_failures, 0,
"Failures to establish the transient mapping due to retry attempts "
"exhausted");
int transient_map_soft_failures;
SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD,
&transient_map_soft_failures, 0,
"Count of retried failures to establish the transient mapping");
int inflight_transient_maps;
SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD,
&inflight_transient_maps, 0,
"Current count of the active transient maps");
static int
g_io_transient_map_bio(struct bio *bp)
{
vm_offset_t addr;
long size;
u_int retried;
KASSERT(unmapped_buf_allowed, ("unmapped disabled"));
size = round_page(bp->bio_ma_offset + bp->bio_length);
KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp));
addr = 0;
retried = 0;
atomic_add_long(&transient_maps, 1);
retry:
if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) {
if (transient_map_retries != 0 &&
retried >= transient_map_retries) {
CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s",
bp, bp->bio_to->name);
atomic_add_int(&transient_map_hard_failures, 1);
return (EDEADLK/* XXXKIB */);
} else {
/*
* Naive attempt to quisce the I/O to get more
* in-flight requests completed and defragment
* the transient_arena.
*/
CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d",
bp, bp->bio_to->name, retried);
pause("g_d_tra", hz / 10);
retried++;
atomic_add_int(&transient_map_soft_failures, 1);
goto retry;
}
}
atomic_add_int(&inflight_transient_maps, 1);
pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size));
bp->bio_data = (caddr_t)addr + bp->bio_ma_offset;
bp->bio_flags |= BIO_TRANSIENT_MAPPING;
bp->bio_flags &= ~BIO_UNMAPPED;
return (EJUSTRETURN);
}
void
g_io_schedule_down(struct thread *tp __unused)
{
struct bio *bp;
int error;
for(;;) {
g_bioq_lock(&g_bio_run_down);
bp = g_bioq_first(&g_bio_run_down);
if (bp == NULL) {
CTR0(KTR_GEOM, "g_down going to sleep");
msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock,
PRIBIO | PDROP, "-", 0);
continue;
}
CTR0(KTR_GEOM, "g_down has work to do");
g_bioq_unlock(&g_bio_run_down);
biotrack(bp, __func__);
if (pace != 0) {
/*
* There has been at least one memory allocation
* failure since the last I/O completed. Pause 1ms to
* give the system a chance to free up memory. We only
* do this once because a large number of allocations
* can fail in the direct dispatch case and there's no
* relationship between the number of these failures and
* the length of the outage. If there's still an outage,
* we'll pause again and again until it's
* resolved. Older versions paused longer and once per
* allocation failure. This was OK for a single threaded
* g_down, but with direct dispatch would lead to max of
* 10 IOPs for minutes at a time when transient memory
* issues prevented allocation for a batch of requests
* from the upper layers.
*
* XXX This pacing is really lame. It needs to be solved
* by other methods. This is OK only because the worst
* case scenario is so rare. In the worst case scenario
* all memory is tied up waiting for I/O to complete
* which can never happen since we can't allocate bios
* for that I/O.
*/
CTR0(KTR_GEOM, "g_down pacing self");
pause("g_down", min(hz/1000, 1));
pace = 0;
}
CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,
bp->bio_to->name);
error = g_io_check(bp);
if (error >= 0) {
CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider "
"%s returned %d", bp, bp->bio_to->name, error);
g_io_deliver(bp, error);
continue;
}
THREAD_NO_SLEEPING();
CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld "
"len %ld", bp, bp->bio_to->name, bp->bio_offset,
bp->bio_length);
bp->bio_to->geom->start(bp);
THREAD_SLEEPING_OK();
}
}
void
g_io_schedule_up(struct thread *tp __unused)
{
struct bio *bp;
for(;;) {
g_bioq_lock(&g_bio_run_up);
bp = g_bioq_first(&g_bio_run_up);
if (bp == NULL) {
CTR0(KTR_GEOM, "g_up going to sleep");
msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock,
PRIBIO | PDROP, "-", 0);
continue;
}
g_bioq_unlock(&g_bio_run_up);
THREAD_NO_SLEEPING();
CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off "
"%jd len %ld", bp, bp->bio_to->name,
bp->bio_offset, bp->bio_length);
biodone(bp);
THREAD_SLEEPING_OK();
}
}
void *
g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
{
struct bio *bp;
void *ptr;
int errorc;
KASSERT(length > 0 && length >= cp->provider->sectorsize &&
length <= MAXPHYS, ("g_read_data(): invalid length %jd",
(intmax_t)length));
bp = g_alloc_bio();
bp->bio_cmd = BIO_READ;
bp->bio_done = NULL;
bp->bio_offset = offset;
bp->bio_length = length;
ptr = g_malloc(length, M_WAITOK);
bp->bio_data = ptr;
g_io_request(bp, cp);
errorc = biowait(bp, "gread");
if (error != NULL)
*error = errorc;
g_destroy_bio(bp);
if (errorc) {
g_free(ptr);
ptr = NULL;
}
return (ptr);
}
/*
* A read function for use by ffs_sbget when used by GEOM-layer routines.
*/
int
g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size)
{
struct g_consumer *cp;
KASSERT(*bufp == NULL,
("g_use_g_read_data: non-NULL *bufp %p\n", *bufp));
cp = (struct g_consumer *)devfd;
/*
* Take care not to issue an invalid I/O request. The offset of
* the superblock candidate must be multiples of the provider's
* sector size, otherwise an FFS can't exist on the provider
* anyway.
*/
if (loc % cp->provider->sectorsize != 0)
return (ENOENT);
*bufp = g_read_data(cp, loc, size, NULL);
if (*bufp == NULL)
return (ENOENT);
return (0);
}
int
g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
{
struct bio *bp;
int error;
KASSERT(length > 0 && length >= cp->provider->sectorsize &&
length <= MAXPHYS, ("g_write_data(): invalid length %jd",
(intmax_t)length));
bp = g_alloc_bio();
bp->bio_cmd = BIO_WRITE;
bp->bio_done = NULL;
bp->bio_offset = offset;
bp->bio_length = length;
bp->bio_data = ptr;
g_io_request(bp, cp);
error = biowait(bp, "gwrite");
g_destroy_bio(bp);
return (error);
}
/*
* A write function for use by ffs_sbput when used by GEOM-layer routines.
*/
int
g_use_g_write_data(void *devfd, off_t loc, void *buf, int size)
{
return (g_write_data((struct g_consumer *)devfd, loc, buf, size));
}
int
g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
{
struct bio *bp;
int error;
KASSERT(length > 0 && length >= cp->provider->sectorsize,
("g_delete_data(): invalid length %jd", (intmax_t)length));
bp = g_alloc_bio();
bp->bio_cmd = BIO_DELETE;
bp->bio_done = NULL;
bp->bio_offset = offset;
bp->bio_length = length;
bp->bio_data = NULL;
g_io_request(bp, cp);
error = biowait(bp, "gdelete");
g_destroy_bio(bp);
return (error);
}
void
g_print_bio(struct bio *bp)
{
const char *pname, *cmd = NULL;
if (bp->bio_to != NULL)
pname = bp->bio_to->name;
else
pname = "[unknown]";
switch (bp->bio_cmd) {
case BIO_GETATTR:
cmd = "GETATTR";
printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute);
return;
case BIO_FLUSH:
cmd = "FLUSH";
printf("%s[%s]", pname, cmd);
return;
case BIO_ZONE: {
char *subcmd = NULL;
cmd = "ZONE";
switch (bp->bio_zone.zone_cmd) {
case DISK_ZONE_OPEN:
subcmd = "OPEN";
break;
case DISK_ZONE_CLOSE:
subcmd = "CLOSE";
break;
case DISK_ZONE_FINISH:
subcmd = "FINISH";
break;
case DISK_ZONE_RWP:
subcmd = "RWP";
break;
case DISK_ZONE_REPORT_ZONES:
subcmd = "REPORT ZONES";
break;
case DISK_ZONE_GET_PARAMS:
subcmd = "GET PARAMS";
break;
default:
subcmd = "UNKNOWN";
break;
}
printf("%s[%s,%s]", pname, cmd, subcmd);
return;
}
case BIO_READ:
cmd = "READ";
break;
case BIO_WRITE:
cmd = "WRITE";
break;
case BIO_DELETE:
cmd = "DELETE";
break;
default:
cmd = "UNKNOWN";
printf("%s[%s()]", pname, cmd);
return;
}
printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd,
(intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
}